VMsafe Firewalls, Are They Real Firewalls or Something More?

The biggest question I ask myself when I see VMsafe appliances is: will it replace my current virtual firewall setup? Replace my Anti-virus? or Both? I am seeing a trend that gives me pause. That is a VMsafe appliance being more than one thing. For example, Trend Micro is an Anti-Virus company that bought Third Brigade (a firewall company) and are now in the mix of merging the two technologies into one. What has happened to one tool that does one thing and does that one thing very well?